TSN support

ABSTRACT

Processes and systems for managing preconfigured resources, in particular wireless transmission resources. The disclosure particularly addresses the management of preconfigured resources in relation to Time Sensitive Network (TSN) data transmission. In addition to allocating periodic preconfigured resources, an allowed transmission window (ATW) is defined. The ATW defines which occurrences of the preconfigured resources may be utilised for transmission, in particular which uplink transmission resources may be utilised by a UE. The ATW may be aligned with the expected time of arrival of TSN data (typically the ingress time window) such that the TSN data can be promptly transmitted. The occurrences which occur outside of the ATW are not to be used for transmission and hence may be re-allocated by the base station for other uses.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International patent applicationPCT/CN2020/074821, filed on Feb. 12, 2020, which claims priority to U.S.Provisional Patent Application No. 62/805,796 filed Feb. 14, 2019, thedisclosures of which are incorporated by reference in their entirety.

TECHNICAL FIELD

The following disclosure relates to methods for configuring ConfiguredGrant Resources, and in particular for configurations relating to TimeSensitive Network configurations.

BACKGROUND

Wireless communication systems, such as the third-generation (3G) ofmobile telephone standards and technology are well known. Such 3Gstandards and technology have been developed by the Third GenerationPartnership Project (3GPP). The 3rd generation of wirelesscommunications has generally been developed to support macro-cell mobilephone communications. Communication systems and networks have developedtowards a broadband and mobile system.

In cellular wireless communication systems User Equipment (UE) isconnected by a wireless link to a Radio Access Network (RAN). The RANcomprises a set of base stations which provide wireless links to the UEslocated in cells covered by the base station, and an interface to a CoreNetwork (CN) which provides overall network control. As will beappreciated the RAN and CN each conduct respective functions in relationto the overall network. For convenience the term cellular network willbe used to refer to the combined RAN & CN, and it will be understoodthat the term is used to refer to the respective system for performingthe disclosed function.

The 3rd Generation Partnership Project has developed the so-called LongTerm Evolution (LTE) system, namely, an Evolved Universal MobileTelecommunication System Territorial Radio Access Network, (E-UTRAN),for a mobile access network where one or more macro-cells are supportedby a base station known as an eNodeB or eNB (evolved NodeB). Morerecently, LTE is evolving further towards the so-called 5G or NR (newradio) systems where one or more cells are supported by a base stationknown as a gNB. NR is proposed to utilise an Orthogonal FrequencyDivision Multiplexed (OFDM) physical transmission format.

The disclosure below relates to various improvements to cellularwireless communications systems.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details, aspects and embodiments of the invention will bedescribed, by way of example only, with reference to the drawings.Elements in the figures are illustrated for simplicity and clarity andhave not necessarily been drawn to scale. Like reference numerals havebeen included in the respective drawings to ease understanding.

FIG. 1 shows a schematic diagram of selected components of a cellularcommunications network;

FIG. 2 shows a schematic diagram of a cellular network as a TSN bridgenode;

FIG. 3 shows a diagram of ingress and egress time windows;

FIG. 4 shows an example of preconfigured resource utilisation;

FIGS. 5 & 6 show examples of preconfigured resource utilisation inrelation to ingress and egress windows;

FIG. 7 shows an example of resources use with an allowed transmissionwindow;

FIG. 8 shows an example of multiple configurations;

FIG. 9 shows an example of resources selected from a frame/boundarypattern;

FIG. 10 shows preconfigured resources with a pseudo-periodic spacing;

FIG. 11 shows an example where the preconfigured resource period is adivisor of the hyperframe length;

FIG. 12 shows an example of resources defined relative to an SFNboundary;

FIG. 13 shows an example with SFN_(start time) being the SFNtimeReferenceSFN; and

FIGS. 14 and 15 exhibit potential difficulties with alternativesolutions.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Those skilled in the art will recognise and appreciate that thespecifics of the examples described are merely illustrative of someembodiments and that the teachings set forth herein are applicable in avariety of alternative settings.

FIG. 1 shows a schematic diagram of three base stations (for example,eNB or gNBs depending on the particular cellular standard andterminology) forming a cellular network. Typically, each of the basestations will be deployed by one cellular network operator to providegeographic coverage for UEs in the area. The base stations form a RadioArea Network (RAN). Each base station provides wireless coverage for UEsin its area or cell. The base stations are interconnected via the X2interface and are connected to the core network via the S1 interface. Aswill be appreciated only basic details are shown for the purposes ofexemplifying the key features of a cellular network. The interface andcomponent names mentioned in relation to FIG. 1 are used for exampleonly and different systems, operating to the same principles, may usedifferent nomenclature.

The base stations each comprise hardware and software to implement theRAN's functionality, including communications with the core network andother base stations, carriage of control and data signals between thecore network and UEs, and maintaining wireless communications with UEsassociated with each base station. The core network comprises hardwareand software to implement the network functionality, such as overallnetwork management and control, and routing of calls and data.

Cellular radio systems may provide methods to configure periodicresources in UL and/or DL. This avoids the need for dynamic grant ofresources as they are required by the UE or base station. Specificexamples of such processes are Semi-Persistent Scheduling (SPS) (UL andDL in LTE, and DL in NR) and Configured Grant Type 1 and Type 2 (CG) (ULin NR). For convenience the generic term preconfigured resources will beutilised to refer to resources configured according to these, orcomparable, processes.

IEEE P802.1Qcc/D1.6 describes various Time Sensitive Network (TSN)configuration models. In a TSN network TSN end stations(Talker/Listener) as well as TSN bridges are synchronised which enablesthe establishment of schedules of TSN flows between TSN end stationssuch that minimal latency is ensured. Particular examples are the fullydistributed, centralised network and distributed user, and centralisednetwork configuration (CNC), and fully centralised models.

TSN traffic is typically periodic, deterministic (bounded latency), aswell as scheduled, i.e. with a known transmission time (and possiblyknown jitter) relative to a time reference. TSN scheduled trafficenhancements are detailed in 802.1Qbv specification.

A TSN bridge supporting scheduled traffic (802.1Qbv) can prioritizetraffic in time windows to reduce latency for traffic received in thosewindows. For such prioritized traffic, the expected latency is very low.In a TSN network, TSN bridges and TSN capable end devices are timesynchronized with high precision (e.g. around 1 us) and share the sameconcept of time, which assists the network to meet the latency andreliability requirements of such traffic. For each TSN flow, a timeschedule can be established within the TSN network such that theend-to-end latency for that flow is guaranteed.

It is possible to configure deterministic periodic traffic from a TSNtalker end station to a TSN listener end station such that the trafficoccurs during specified periodic time windows. Each TSN bridge in theTSN network guarantees the latency for incoming traffic during suchingress windows, and also ensures transmission of the traffic within aspecified egress window to the next node in the network.

Integration of cellular systems, in particular 5G/NR, has beenconsidered and defined by specifying that cellular systems (includingUE, RAN, and Core Network) will appear as a TSN bridge (black box). Thecellular system utilises a QoS framework in which applications canrequest QoS properties that the cellular system meets according to itsoperating methods. FIG. 2 shows an example model of a cellular systemacting as a bridge, with UPF on one side and UE(s) on the other side aspart of a common TSN bridge

FIG. 3 shows a diagram of TSN traffic flow through a TSN bridge. TheTraffic Periodicity (TP) 200 defines the period between Ingress TimeWindows (ITW) 201 within which data can be expected to arrive at the TSNbridge. The ITW is the window around an arrival time created due to thearrival time offset and jitter. The Egress Time Window (ETW) 202represents the window in which data received in a corresponding ITW willbe output from the TSN bridge and is negotiated during establishment ofthe schedule by the TSN bridge.

The TSN bridge may also be aware of other parameters such as messagesize, and reference time or offset.

As noted above, preconfigured resources may be allocated for a UE.Specific examples of which are CG and SPS. Preconfigured resources areperiodic time/frequency transmission resources allocated fortransmission of data in UL or DL. The periodicity and location in timeof the resources is defined by the RAN radio frame structure (slots/OFDMsymbols). Preconfigured resources have 2 main different use cases:support of periodic traffic (examples is 20 ms periodicity defined fortransport of voice traffic), and support of low latency sporadictraffic, by skipping transmission when there is no data to be send(example is 1 ms for providing low latency).

TSN traffic is expected to be both periodic and latency critical, withknown sending time (traffic time offset). It is expected that 5GS,acting as a TSN bridge, is synchronized with high precision to other TSNdevices in the network so that all devices share the same concept oftime.

When carrying TSN data using preconfigured resources the latency andjitter introduced may be dependent on the periodicity of the assignedresources and the relationship of that period with the TSN data arrivaltimes.

In order to ensure transmission latency below a budget L (at RAN level),CG with periodicity P lower than L can be configured (taking intoaccount additional margin delay such as transmission time or delay dueto retransmissions). The periodicity P can hence be directly setaccording to the lowest required latency of the traffic to be supportedby the corresponding CG/SPS configuration.

Whenever TSN traffic periodicity matches an available CG periodicity,the transmission latency can be reduced as desired by adjusting the CGtime offset, without resource waste (See FIG. 14 ).

Whenever TSN traffic periodicity matches a CG periodicity multiple, thetransmission latency can also be reduced as desired by adjusting the CGtime offset, similarly as above. We consider as an example a trafficperiodicity (TP) of 15 ms. The CG periodicity 15 ms is not supported;however, 5 ms is supported and may be used to match the trafficperiodicity. Contrary to previous case, the drawback is a waste ofreserved resources (See FIG. 15 ).

As CG periodicity is related to RAN radio frame structure, in generalthere is no guarantee that TSN traffic periodicity matches available CGperiodicities (including their multiples). In 802.11Qbv, the cycle timeis a rational number of seconds, defined by an integer numerator and aninteger denominator (both UINT32), i.e., the cycle duration is anarbitrary rational number of seconds.

In this case, there will be a drift between the CG pattern and thetraffic pattern. Hence, the approach based on adjusting CG time offsetis not possible to control the latency, unless frequent adjustment aremade to compensate for the drift between both patterns. Such frequentadjustments are not desirable as they increase the control traffic andthe risk of configuration error, for a traffic which has not only tightlatency requirements but also very high reliability requirements.

In order to ensure transmission latency below a budget L (at RAN level),the periodicity P of preconfigured resources must be lower than value L,as shown in FIG. 4 . The periodicity of resources can thus be definedbased on the minimum latency required for the traffic to be supported bythe preconfigured resources, taking into account additional margin delaysuch as transmission time or delay due to retransmissions. Although thisensures latency requirements are met, it may be inefficient in terms ofresource utilisation. To ensure the latency requirements are met theperiod P of the preconfigured resources may be substantially less thanthe TSN traffic period, and hence multiple preconfigured resources occurin each TSN traffic period which are not required, as shown in FIG. 4 .

Once assigned for a UE, preconfigured resources are not directly mappedfor a TSN traffic flow and hence the system may not be aware of whichresources will be used. This prevents re-use of unused resources. Forexample, for UL TSN traffic a base station may not be aware whichpreconfigured resources the UE will use and hence cannot allocate unusedresources for other purposes.

Another alternative is to match the resource pattern with the trafficpattern. The effective allocated resource is then the first in timeassociated to a SymbolIndex (or SlotIndex) following (and including) theSymbolIndex derived by CG or SPS formula, and which is also allowed bythe corresponding physical layer PUSCH or PDSCH configuration. As aresult, the SPS/CG would no longer be periodic (in terms of symbols orslots), but pseudo-periodic, as shown in FIG. 10 .

Such an approach may allow preconfigured resources to match more closelythe TSN traffic pattern. This allows latency to be reduced and resourceefficiency increased. However, the approach may lack flexibility, as theresource allocated is “the next in time allowed by the correspondingPUSCH or PDSCH configuration”, for which the configuration is limited(it is configured only by the corresponding UL grant or DL assignment).For instance, a given traffic may not need the lowest possible latencywhich is provided by this scheme.

As it can be seen, in case of unmatched Traffic Periodicity/CGPeriodicity (or multiple thereof), the following issues appear:

frequent CG time offset adjustments or,

impeded time multiplexing capabilities (if CG periodicity is extended tomatch traffic periodicity)

important resource waste (if CG periodicity matching required latency ispreferred).

An additional potential issue (See FIG. 5 ) is that the egress timewindow (after the RAN of the cellular network forming the TSN bridge)may be larger than the ingress time window. That is, the RAN may notonly add latency but also jitter. In cases where a cellular network isintegrated into a TSN network, connected for instance to a further TSNbridge, it could be desired that the ingress time window of this furtherTSN bridge is short, i.e. that the egress time window of the cellularnetwork bridge is short. The egress time window enforcement could berealized at higher layers of the cellular network (out of the RAN), forinstance in the TSN translator interfacing with the TSN system. Thatwould mean in such case that the cellular system has to hold on topackets transmitted “too fast” by the RAN before forwarding them out ofthe cellular network. This reduces jitter but increases latency for somedata. It is preferable instead to relax RAN requirements to enablebetter usage of radio resources.

Given the knowledge of TSN traffic, it is possible to avoid resourcewaste by constraining the UE to transmit only on specific occasions, orequivalently in defined windows—i.e. to ensure that the CG pattern doesnot provide transmit occasions which will (most of the time) not beused. This can be achieved by only providing preconfigured resourceswithin those windows, and not elsewhere. Provided the TSN trafficpattern is known, the preconfigured resources should not need to bedynamically adjusted in order to avoid additional frequent controlsignalling.

As described earlier, the CG is used mainly for either periodic or lowlatency traffic. The corresponding time configuration (periodicity/timeoffset) has to be set according either to traffic periodicity, or totraffic latency requirement.

TSN traffic has both periodic pattern and low latency requirements,which may be handled efficiently by existing preconfigured resourceallocations. It would be beneficial to enhance existing preconfiguredresource allocation processes so that they encompass both theconstraints of the RAN frame structure and of the TSN traffic. For thispurpose, the preconfigured resource configuration may be enhanced suchthat it is based on both:

-   -   A boundary/resource pattern (periodicity/time offset), aligned        with RAN frame structure, which can be used to ensure the        desired latency requirement is met.    -   A traffic/allowed transmission pattern (periodicity/time        offset), which can be used to match the traffic pattern, and may        have an arbitrary periodicity

Two potential options to enhance existing preconfigured resourceallocations:

-   -   Consider the existing preconfigured resource pattern as the        boundary/resource pattern, and add an “allowed transmission        window” pattern.    -   Extend the existing preconfigured resource pattern so that it        can be used as the traffic pattern, and define a        boundary/resource pattern to select the resource.

Both options are described in further details below.

A first option considers introducing an Allowed Transmission Window. Inorder to efficiently manage preconfigured resources a window, forexample “Allowed Transmission Window (ATW)” may be configured inaddition to the periodic preconfigured resources. Preconfiguredresources falling within the ATW are for use as allocated, whereaspreconfigured resources falling outside of the ATW are not to beutilised as allocated and the resources may be utilised by the basestation for a different purpose. Such a system is most likely to beapplied to preconfigured uplink resources as the base station does nototherwise have awareness the resources will not be used. The provisionof the ATW enables the base station to use the preconfigured resourcesfor another purpose, for instance to allocate them to a different UE,without a risk of collision with an uplink transmission in theresources. However, the principles may be applied to uplink and downlinkresources of any configuration.

The ATW pattern may be defined based on the TSN traffic schedule, suchas periodicity and time offset, as well as ingress and egress timewindows.

The ATW pattern may be defined by a set of parameters, for example,window periodicity, offset, and length.

The ATW periodicity should be configurable to correlate with anticipatedTP of the TSN data flow. The period should there by a rational numberseconds wherein the timing is radio timing (1 s=100 radio frames). Saidanother way, the periodicity may be a rational number of radio frames.

The window offset may be defined relative to SFN 0 of the radiohyperframe, defined as a rational number of seconds or radio frames(e.g. by signalling a numerator and denominator). If the period is adivisor of the hyperframe length the offset may relative to the same SFNin each hyperframe, for example SFN 0. If the period is not a divisor ofthe hyperframe the offset may be relative to a SFN which depends on thehyperframe, as explained in more detail below.

The length of the ATW may be defined as a duration in time (e.g. numberof symbols or a rational number of subframes, or as a number of grantsof the preconfigured resources (with a minimum of 1).

These parameters permit all relevant aspects of the ATW to be defined tounambiguously specify which resources are available in a period cycle.Some or all of the parameters may be predefined and static to reducecontrol overhead.

The ATW may be configured and communicated by an RRC process andmessaging together with the preconfigured resources configuration, orwith an RRC LCH configuration, for example as part of mappingrestrictions. For example, the ATW may only allow mapping of an LCH topreconfigured resources within the ATW which has an equivalent effect ofpreventing use of the preconfigured outside of the ATWs.

When an ATW is configured, MAC maintains a periodic allowed transmissionwindow pattern, related to UL preconfigured resources or related to anLCH mapping rule. After deriving possible UL preconfigured resourcesfrom the UL preconfigured resources configuration, the MAC may consideras valid only the ones allowed by the ATW.

As noted above, the ATW must be defined unambiguously to identify whichpreconfigured resources part of the underlying CG or SPS pattern areavailable for use, i.e. are effectively preconfigured resources. As itis desirable for the ATW to match the likely TP the ATW might start atany time, including at a fractional number of subframes. A possible ruleis to translate this timing to symbols using 1 radioframe=numberOfSlotsPerFrame×numberOfSymbolsPerSlot.

That is, the window is defined assuming symbols are evenly distributedwithin a slot. It doesn't matter if at the physical level the timing atsymbol level is slightly different (for example due to cyclic prefix)since the rule is only used to identify without any ambiguity whichpreconfigured resources fall within the ATW, and which ones are outside.

As discussed above, the length of the ATW may be defined. The length maybe defined as a time duration (e.g. number of symbols or a rationalnumber of subframes).

In case an Allowed Transmission Window is configured, MAC maintains anallowed transmission window pattern as follows

After an allowed transmission window is configured for a configuredgrant, the MAC entity may consider sequentially that an allowedtransmission window starts associated with the symbol for which:—[(SFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)+(slot number in theframe×numberOfSymbolsPerSlot)+symbol number in theslot]=Floor[(SFN_(start time)+TransmitWindowTimeOffset+N×TransmitWindowPeriodicity)×numberOfSlotsPerFrame×numberOfSymbolsPerSlot]modulo(1024×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)

And that it ends associated with the symbol for which:—[(SFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)+(slot number in theframe×numberOfSymbolsPerSlot)+symbol number in theslot]=Floor[(SFN_(start time)+TransmitWindowTimeOffset+TransmitWindowLength+N×TransmitWindowPeriodicity)×numberOfSlotsPerFrame×numberOfSymbolsPerSlot]modulo(1024×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)

where SFN_(start time) is the SFN timeReferenceSFN immediately precedingthe reception of the preconfigured resources configuration.

The MAC entity thus utilises (for example by only retaining details of)preconfigured resources from the corresponding CG or SPS pattern with asymbol index that falls with in the allowed transmission window. Forinstance when an Allowed Transmission Window is configured for aconfigured grant, MAC shall retain only the UL grants of the CGassociated with a symbol index which falls within an allowedtransmission window, and ignore other UL grants of the CG.

As will be apparent, ceil operations may be utilised instead of thefloor example above.

FIG. 6 shows an example in which ATWs 500 are defined with a periodaligned to the TP. The ATW provides two occurrences 501 of preconfiguredresources that fall within the ATW and which are therefore available foruse for TSN traffic, followed by a number of occurrences 502 which arenot available as they fall outside of the ATW. The number of unavailableoccurrences 502 may vary depending on the alignment of the ATW with thepreconfigured resources.

The length of the ATW may also be defined based on a number ofoccurrences of preconfigured resources. In case an Allowed TransmissionWindow is configured, MAC maintains an allowed transmission windowpattern as follows:—

After an allowed transmission window is configured for a configuredgrant, the MAC entity may consider sequentially that an allowedtransmission window starts associated with the symbol for which:[(SFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)+(slot number in theframe×numberOfSymbolsPerSlof)+symbol number in theslot]=Floor[(SFN_(start time)+TransmitWindowTimeOffset+N×TransmitWindowPeriodicity)×numberOfSlotsPerFrame×numberOfSymbolsPerSlot]modulo(1024×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)

where SFN_(start time) is the SFN timeReferenceSFN immediately precedingthe reception of the preconfigured resources configuration.

When an ATW is configured with a length TransmitWindowLength the MACentity retains only the TransmitWindowLength first consecutiveoccurrences of the preconfigured resources from the preconfiguredresources associated with a symbol index equal or following the symbolassociated to an allowed transmission window start, and ignore otherpreconfigured resources.

Alternatively, it could be considered that instead of TransmissionWindow Start, Transmission Window End is indicated, and that the MACentity retains only the TransmitWindowLength last consecutiveoccurrences of the preconfigured resources from the preconfiguredresources associated with a symbol index preceding the symbol associatedto an allowed transmission window end, and ignore other preconfiguredresources. This could for instance be used to better match the resourcewith an egress window, rather than match the resources with an ingresswindow.

FIG. 7 shows an example in which TransmitWindowLength is equal to oneoccurrence of the preconfigured resources. More than one preconfiguredresources configuration may be supported to permit sending of Krepetitions for any start time offset, as shown in FIG. 8 . For suchconfigurations, it may be beneficial to consider such multipleconfigurations set as a bundle of configurations providing transmissionopportunities (possible preconfigured resources) with a reducedperiodicity (P/4 in FIG. 8 ). This enables only one ATW configuration tobe defined for the multiple preconfigured resource configurations.

A second option considers extending the CG or SPS periodicity. The cycletime defined for TSN data (in 802.1Qbv) is a rational number of seconds,defined by an integer numerator and an integer denominator (both UINT32in this example). That is, the cycle is a rational number of seconds.The cycle time may therefore not match a symbol or slot period and so amore flexible definition of periodic resources may be beneficial whichis not perfectly regular to best align with the TSN cycle. A rationaltraffic period may thus be defined by signalling a numerator anddenominator

In particular examples, periodic the SPS or CG could be extended tosupport rational traffic period P as set out in more detail below.Similarly, as described above, the formula can be reused to deliver arational SymbolIndex (CG, SPS if the granularity is enhanced) orSlotIndex (SPS). A floor or ceil operation can be used to identifywithout ambiguity the SymbolIndex (or SlotIndex).

The formula for location of preconfigured resources then indicatesarbitrary time instants (possibly as a fraction of symbols) not matchingan actual resource:—SymbolIndex_Within_HF=SymbolOffsetFromRefWithin_P+N*P moduloSymbols_Per_HF

To determine the preconfigured resource to be utilised for transmissionof traffic, a boundary/resource pattern (i.e a pattern aligned with theRAN frame structure) would be used in which preconfigured resources arealigned with the RAN frame structure. The earliest resource from thatpattern following an indicated Symbol, as shown in FIG. 9 , would beselected.

This approach may ensure that a latency target can be met by defining anappropriate period for the preconfigured resources, but unrequiredresources are available for other uses. In an alternative, the firstavailable resource, according to fixed rules such as next slot boundary(instead of having it selected from a resource pattern), could beselected but this would impair time multiplexing of different patterns(e.g. for other UEs), since possibly all transmit opportunity timeoffsets would end up being selected. On the contrary, using anadditional resource pattern enable to optimize the resource utilizationsuch as the latency requirement is still fulfilled, but timemultiplexing is not impaired (in above example, all other resource timeoffsets are free to be used for other patterns).

As an option, the number of consecutive resources (i.e. transmissiongrants) configured at each period may be configured as well. Thisenables the system to handle traffic with a known ingress window(arrival time+jitter) with lower latency. When N consecutive grants areconfigured, such grants may be configured from the boundary/resourcepattern, by considering (selecting) N consecutive grant resources,starting for instance from the earliest resource from that patternfollowing or including the indicated Symbol.

In another option, assuming the gNB knows the egress window (leavingtime, with possibly associated jitter), the pattern may be definedrelative to such leaving time. In this case, instead of considering theearliest resource(s) from the resource pattern after the indicatedsymbol, it should be possible to consider the latest resource(s) fromthe resource pattern before the indicated symbol.

Additional flexibility may be gained by accommodating preconfiguredgrant periodicities or ATW periodicities that are not divisors of thehyperframe length.

As shown in FIG. 11 when the preconfigured grant period is a divisor ofthe hyperframe length the resource locations can be defined as an offsetfrom SFN 0, which gives the same position in each hyperframe. However,as shown in FIG. 10 , if the period is not a divisor of the hyperframelength the position of preconfigured resources various depending on thenumber of hyperframes from the first occurrence. The UE must thus knowwhich hyperframe boundary defines SFN 0 from which the offset isdefined.

This difficulty may be addressed by ensuring the base station onlytransmits a configuration message (for example an RRC message)sufficiently early in a hyperframe to ensure it is received andprocessed prior to the start of the next hyperframe. The correct SFN 0is thus indicated implicitly by the transmission time of theconfiguration message. However, such a system requires close interactionof the indication (for example RRC message) with the SFN (layer 1)timing, which is undesirable. The method also limits the opportunitiesfor a base station to transmit the configuration message.

In an alternative option the configuration message (for example RRCmessage) a time reference may be indicated from which the offset isapplied. The time reference may be an SFN, optionally in the future, ora part of the SFN which can identify a location unambiguously (forexample a set number of the MSBs of the SFN). In an example only the MSBmay be utilised indicating either the next SFN 0 boundary or the nextSFN 512 (middle of a hyperframe) boundary. This gives up to 5.12 s oflatency for correct identification which is anticipated to be muchhigher than the expected RRC latency.

In the example of FIG. 11 the RRC configuration message would indicatethe SFN 512 boundary, whereas the RRC configuration message of FIG. 12would indicate the SFN 0 boundary, as these are the next relevantboundaries after the configuration message. The configuration message(in this example only an RRC message) must be transmitted sufficientlyin advance of the indicated boundary to be received and actioned.

In addition to existing RRC parameters for CG Type 1, RRC could alsoconfigure timeReferenceSFN: Time reference SFN. If the existing formulaadds this offset (converted into symbols) to the existing time offsettimeDomainOffset×numberOfSymbolsPerSlot+S, as follows, after an uplinkgrant is configured for a configured grant Type 1, the MAC entity shallconsider that the uplink grant recurs associated with each symbol forwhich:[(SFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)+(slot number in theframe×numberOfSymbolsPerSlot)+symbol number in theslot]=(timeReferenceSFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot+timeDomainOffset×numberOfSymbolsPerSlot+S+N×periodicity)modulo(1024×numberOfSlotsPerFrame×numberOfSymbolsPerSlot),for all N>=0.

the result on FIG. 12 would be a superposition of all preconfiguredresources.

In order to avoid delays in the activation of preconfigured resourcesthe initial formula may be adapted as follows. After an uplink grant isconfigured for a configured grant Type 1, the MAC entity shall considersequentially that uplink grants occur associated with the symbol forwhich:[(SFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)+(slot number in theframe×numberOfSymbolsPerSlot)+symbol number in theslot]=(SFN_(start time)×numberOfSlotsPerFrame×numberOfSymbolsPerSlot+timeDomainOffset×numberOfSymbolsPerSlot+S+N×periodicity)modulo(1024×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)

where SFN_(start time) is the SFN timeReferenceSFN immediately precedingthe reception of the configured grant Type 1 configuration.

Equivalently, where SFN_(start time) is the SFN timeReferenceSFNimmediately following the reception of the configured grant Type 1configuration (assuming N can be negative in the formula).

FIG. 13 shows an example with SFN_(start time) being the SFNtimeReferenceSFN immediately preceding the reception of the configuredgrant Type 1 configuration.

The same mechanism can be used to configure with RRC an AllowedTransmission Window Periodicity not dividing the HF length.

Within the TSN network, it is expected that for a TSN flow, the 5GS canhave TSN flow traffic information such as periodicity, but also (seeFIG. 3 ): ingress (arrival) time window (or equivalently, arrival timeoffset and jitter around the arrival time). egress time window (asnegotiated during the schedule establishment) (or equivalently, leavingtime offset and jitter around the leaving time)

It is proposed that in addition to already discussed traffic informationsuch as periodicity, message size, reference time or offset, the gNB isalso made aware of the ingress time window (size/offset, or equivalentlyjitter around the arrival time) and/or egress time window (as negotiatedduring the schedule establishment), or equivalently, leaving time offsetand jitter around the leaving time).

This information can be leveraged to enhance scheduling, as described inother parts of the proposal.

The knowledge of ingress time window allows configuring resources withinthe window, thereby reducing the latency.

The knowledge of egress time window allows relaxing RAN requirements toenable better usage of radio resources. For instance, assuming aperiodic traffic with a fixed leaving time pattern, this informationcould be used by the RAN to configure 1 resource before each leavinginstant time.

In order to avoid wasting preconfigured resources when no TSN data isavailable, the preconfigured resources can be deactivated/reactivatedoutside of each ingress time window. However, such a process willincrease control signalling overhead, and there is a risk of failedreactivation which would lead to significantly increased latency. Theneed for control signalling could be reduced by including a windowlength, or number of repetitions of the preconfigured resources, whenactivating the resources such that the preconfigured resources are onlyactivated for that window or number of repetitions. This removes theneed for a deactivation message (for example a DCI), but thereactivation message is still required which represents a large portionof the control signalling overhead and still retains the risk of a lostsignal.

In order to mitigate the overhead a suspend state may be introduced inwhich the configured grant resources (e.g. CG Type 2) configurationremains stored but is not active (i.e. not delivered to the HARQentity). The configuration is defined such that the preconfiguredresources automatically transition to the suspended state after aconfigured window length or number of repetitions of the preconfiguredresources. A message is then utilised to resume active operation basedon the prior configuration, for example a DCI message may betransmitted. The DCI used for deactivation might be reused forresumption, relying for instance on the fact that deactivation is nolonger needed due to the new autonomous suspension mechanism. Themessage to resume operation may also adjust parameters of thepreconfigured resources, for example the time offset, for example tobetter match traffic patterns. Such techniques may be principallyrelevant to CG Type 2 configurations but may also apply to otherpreconfigured resources such as CG type 1. The reduced signallingoverhead may still be significant depending on the TSN parameters.

In 802.11Qbv, TSN traffic is based on a cyclic pattern, each patterndefined by on-off periods which can be of any size or offset. The abovepatterns may be extended to include such cyclic patterns. Alternatively,using multiple CG also enables to implement such patterns.

The ATW described hereinbefore may be configured for a group of UEssharing the same time restrictions. For such configuration, group basedsignaling could be used, either dedicated or broadcasted. This mayenable for instance to restrain group of UEs to transmit only duringspecific time windows.

There are therefore provided a number of processes and systems formanaging preconfigured resources, in particular wireless transmissionresources. The disclosure particularly addresses the management ofpreconfigured resources in relation to Time Sensitive Network (TSN) datatransmission. In addition to allocating periodic preconfiguredresources, an allowed transmission window (ATW) is defined. The ATWdefines which occurrences of the preconfigured resources may be utilisedfor transmission, in particular which uplink transmission resources maybe utilised by a UE. The ATW may be aligned with the expected time ofarrival of TSN data (typically the ingress time window) such that theTSN data can be promptly transmitted. The occurrences which occuroutside of the ATW are not to be used for transmission and hence may bere-allocated by the base station for other uses. The ATW may be definedby its offset from a defined boundary, for example a hyperframeboundary. The boundary may be SFN 0, or another SFN within thehyperframe. The length and periodicity of the ATW may also be defined.The ATW may be communicated to a UE using a configuration message, forexample an RRC message. The configuration message may indicate theboundary from which an offset is defined. For example, the message mayindicate that the boundary is the next occurrence of a defined SFN.

Although not shown in detail any of the devices or apparatus that formpart of the network may include at least a processor, a storage unit anda communications interface, wherein the processor unit, storage unit,and communications interface are configured to perform the method of anyaspect of the present invention. Further options and choices aredescribed below.

The signal processing functionality of the embodiments of the inventionespecially the gNB and the UE may be achieved using computing systems orarchitectures known to those who are skilled in the relevant art.Computing systems such as, a desktop, laptop or notebook computer,hand-held computing device (PDA, cell phone, palmtop, etc.), mainframe,server, client, or any other type of special or general purposecomputing device as may be desirable or appropriate for a givenapplication or environment can be used. The computing system can includeone or more processors which can be implemented using a general orspecial-purpose processing engine such as, for example, amicroprocessor, microcontroller or other control module.

The computing system can also include a main memory, such as randomaccess memory (RAM) or other dynamic memory, for storing information andinstructions to be executed by a processor. Such a main memory also maybe used for storing temporary variables or other intermediateinformation during execution of instructions to be executed by theprocessor. The computing system may likewise include a read only memory(ROM) or other static storage device for storing static information andinstructions for a processor.

The computing system may also include an information storage systemwhich may include, for example, a media drive and a removable storageinterface. The media drive may include a drive or other mechanism tosupport fixed or removable storage media, such as a hard disk drive, afloppy disk drive, a magnetic tape drive, an optical disk drive, acompact disc (CD) or digital video drive (DVD) read or write drive (R orRW), or other removable or fixed media drive. Storage media may include,for example, a hard disk, floppy disk, magnetic tape, optical disk, CDor DVD, or other fixed or removable medium that is read by and writtento by media drive. The storage media may include a computer-readablestorage medium having particular computer software or data storedtherein.

In alternative embodiments, an information storage system may includeother similar components for allowing computer programs or otherinstructions or data to be loaded into the computing system. Suchcomponents may include, for example, a removable storage unit and aninterface, such as a program cartridge and cartridge interface, aremovable memory (for example, a flash memory or other removable memorymodule) and memory slot, and other removable storage units andinterfaces that allow software and data to be transferred from theremovable storage unit to computing system.

The computing system can also include a communications interface. Such acommunications interface can be used to allow software and data to betransferred between a computing system and external devices. Examples ofcommunications interfaces can include a modem, a network interface (suchas an Ethernet or other NIC card), a communications port (such as forexample, a universal serial bus (USB) port), a PCMCIA slot and card,etc. Software and data transferred via a communications interface are inthe form of signals which can be electronic, electromagnetic, andoptical or other signals capable of being received by a communicationsinterface medium.

In this document, the terms ‘computer program product’,‘computer-readable medium’ and the like may be used generally to referto tangible media such as, for example, a memory, storage device, orstorage unit. These and other forms of computer-readable media may storeone or more instructions for use by the processor comprising thecomputer system to cause the processor to perform specified operations.Such instructions, generally 45 referred to as ‘computer program code’(which may be grouped in the form of computer programs or othergroupings), when executed, enable the computing system to performfunctions of embodiments of the present invention. Note that the codemay directly cause a processor to perform specified operations, becompiled to do so, and/or be combined with other software, hardware,and/or firmware elements (e.g., libraries for performing standardfunctions) to do so.

The non-transitory computer readable medium may comprise at least onefrom a group consisting of: a hard disk, a CD-ROM, an optical storagedevice, a magnetic storage device, a Read Only Memory, a ProgrammableRead Only Memory, an Erasable Programmable Read Only Memory, EPROM, anElectrically Erasable Programmable Read Only Memory and a Flash memory.In an embodiment where the elements are implemented using software, thesoftware may be stored in a computer-readable medium and loaded intocomputing system using, for example, removable storage drive. A controlmodule (in this example, software instructions or executable computerprogram code), when executed by the processor in the computer system,causes a processor to perform the functions of the invention asdescribed herein.

Furthermore, the inventive concept can be applied to any circuit forperforming signal processing functionality within a network element. Itis further envisaged that, for example, a semiconductor manufacturer mayemploy the inventive concept in a design of a stand-alone device, suchas a microcontroller of a digital signal processor (DSP), orapplication-specific integrated circuit (ASIC) and/or any othersub-system element.

It will be appreciated that, for clarity purposes, the above descriptionhas described embodiments of the invention with reference to a singleprocessing logic. However, the inventive concept may equally beimplemented by way of a plurality of different functional units andprocessors to provide the signal processing functionality. Thus,references to specific functional units are only to be seen asreferences to suitable means for providing the described functionality,rather than indicative of a strict logical or physical structure ororganisation.

Aspects of the invention may be implemented in any suitable formincluding hardware, software, firmware or any combination of these. Theinvention may optionally be implemented, at least partly, as computersoftware running on one or more data processors and/or digital signalprocessors or configurable module components such as FPGA devices.

Thus, the elements and components of an embodiment of the invention maybe physically, functionally and logically implemented in any suitableway. Indeed, the functionality may be implemented in a single unit, in aplurality of units or as part of other functional units. Although thepresent invention has been described in connection with someembodiments, it is not intended to be limited to the specific form setforth herein. Rather, the scope of the present invention is limited onlyby the accompanying claims. Additionally, although a feature may appearto be described in connection with particular embodiments, one skilledin the art would recognise that various features of the describedembodiments may be combined in accordance with the invention. In theclaims, the term ‘comprising’ does not exclude the presence of otherelements or steps.

Furthermore, although individually listed, a plurality of means,elements or method steps may be implemented by, for example, a singleunit or processor. Additionally, although individual features may beincluded in different claims, these may possibly be advantageouslycombined, and the inclusion in different claims does not imply that acombination of features is not feasible and/or advantageous. Also, theinclusion of a feature in one category of claims does not imply alimitation to this category, but rather indicates that the feature isequally applicable to other claim categories, as appropriate.

Furthermore, the order of features in the claims does not imply anyspecific order in which the features must be performed and in particularthe order of individual steps in a method claim does not imply that thesteps must be performed in this order. Rather, the steps may beperformed in any suitable order. In addition, singular references do notexclude a plurality. Thus, references to ‘a’, ‘an’, ‘first’, ‘second’,etc. do not preclude a plurality.

Although the present invention has been described in connection withsome embodiments, it is not intended to be limited to the specific formset forth herein. Rather, the scope of the present invention is limitedonly by the accompanying claims. Additionally, although a feature mayappear to be described in connection with particular embodiments, oneskilled in the art would recognise that various features of thedescribed embodiments may be combined in accordance with the invention.In the claims, the term ‘comprising’ or “including” does not exclude thepresence of other elements.

The invention claimed is:
 1. A method for a configuration ofpreconfigured transmission resources in a cellular communicationsnetwork, the method comprising the steps of: configuring periodictransmission resources for transmission of data from a mobile device toa base station; and transmitting an indication of the periodictransmission resources from the base station to the mobile device in aconfiguration message, wherein the indication includes an offset(TimeDomainOffset) from a time reference SFN (timeReferenceSFN) to theperiodic transmission resources, wherein the time reference indicates amost recent previous occurrence of a System Frame Number (SFN) prior toa reception of the configuration message.
 2. The method according toclaim 1, wherein the configuration message includes the time reference.3. The method according to claim 1, wherein the time reference isindicated implicitly by a transmission time of the configurationmessage.
 4. The method according to claim 1, wherein a period of thetransmission resources is not a divisor of a hyperframe length which is1024 sub frames.
 5. The method according to claim 1, wherein the timereference is SFN 0 or SFN
 512. 6. The method according to claim 1,wherein after an uplink grant is configured for a configured grant Type1, a MAC entity shall consider that the uplink grant recurs associatedwith each symbol for which:[(SFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot)+(slot number in theframe×numberOfSymbolsPerSlot)+symbol number in theslot]=(timeReferenceSFN×numberOfSlotsPerFrame×numberOfSymbolsPerSlot+timeDomainOffset×numberOfSymbolsPerSlot+S+N×periodicity)modulo (1024×numberOfSlotsPerFrame×numberOfSymbolsPerSlot), for all N>=0.